The aim of this study was correlate clinical, biochemistry, serological and molecular features of delta hepatitis in patients that were registered in outpatient service for hepatites in Rondônia State, Brazilian Western Amazon Region, from october 1993 to october 2004. One hundred nine patients with HBsAg and anti-HDV positive by enzyme-linked immunosorbent assay, was registered 67 males and 42 females, ages between nine and 75 years old. The associate with risk fators was observed in one patient endovenous drug addict and sixteen with blood transfusion history. High prevalence of anti-HDV was verified between 31 to 40 years old. The anti-HBc IgM positive in five samples is probably coinfection and presence of HBeAg in one sample indicated active replication. We had develop a RT-PCR based molecular assay to confirm the diagnostic of delta virus infection. Only in six of 30 analysed serum, was detected the HDV-RNA, probably due the condictions of storage of the samples. The liver function tests, alanine aminotransferase and aspartate aminotransferase, were higher in the group of HDV-RNA positive than those without HDV-RNA. Others eighteen serum samples were selected for genotyping in the National Institute of Health and Medical Research located in Lyon (França), by RT-PCR, Southern Blotting and Hibridization genotype-specific. The results showed genotype I in four samples and genotype III in seven. During eleven years of clinical attendance, the Hepatitis Outpatient Service have registered 24 death of delta hepatitis patients. In Rondonia State, this disease manifest different clinical pictures: asympyomatic cases, chronic liver disease and liver cirrhosis. Determination of HDV-RNA can be of great value for the precise diagnosis and monitoring of the chronic delta hepatitis in these patients.